Black smoke billowed into the night sky from Sistine Chapel's chimney signaling inconclusive first vote in the conclave to elect a new pope. Rough Cut (no reporter narration).

BLACK smoke billowed out of the Vatican chimney today signifying the first ballot to elect a pope to lead the world's 1.2 billion Catholics had failed to find a single leading candidate.

Thousands braved teeming rain and at times hail to cower under umbrellas in St Peter’s Square to look to the heavens and watch the small chimney high above the Sistine Chapel for a sign of election progress.

White smoke, signifying a pope has been chosen, was never likely in this first ballot but the conclave has attracted huge global attention since Pope Benedict, 85, made history last month by becoming the first pope in 600 years to step down.

The black smoke, created from the burning of the ballots in a stove in the chapel and aided by some added chemicals including potassium and sulphur, billowed above the Vatican terracotta roof tops shortly after 7.50pm local time. Many in the St Peter's Square on what was a unseasonally cold evening, carried flags of their papal hopes including banners from Spain, Philippines, Brazil and Mexico as well of course from Italy.

There was great anticipation despite the expectation there would not be a result but consensus was being part in a moment in history.

Four ballots will now be held every day until consensus is built upon and a candidate attracts a two thirds majority or at least 77 votes to be elected pope; no clear favourite has been identified although cardinal Angelo Scola and Brazil's Odilo Scherer are seen as frontrunners.

Cardinals attend a mass at the St Peter's basilica before the start of the conclave. AFP PHOTO / GABRIEL BOUYS

The papal tailor Gammarelli delivered the clothes on Monday to ensure that the newly elected pope could change immediately into papal white as soon as he accepts the election. With the words "Habemus Papam'' - or "We have a pope'' - the pontiff then appears on the balcony of St. Peter's Basilica to greet the crowd for the first time.

A group of women who say they are priests launched pink smoke from a balcony overlooking the square during the Mass to demand female ordination - a play on the famous smoke signals that will tell the world whether a pope has been elected.

And in a bizarre twist, basketball star Dennis Rodman is expected to arrive in St. Peter's Square tomorrow in a makeshift popemobile as he campaigns for Cardinal Peter Turkson of Ghana to become the church's first black pope.

Earlier in the afternoon, the 115 cardinals from around the world eligible to vote attended a moving Gregorian-chanting mass to pray the Holy Spirit guided them in their important election of a new pope to lead the church which has been bogged in corruption, controversy, politics and scandal in recent times. They were joined by thousands of devout pilgrims and clergy from a myriad of religious orders all wearing their traditional robes.

During the mass homily, Cardinal Angelo Sodano, dean of the college of cardinals, alluded to the disunity within the fractured church, appealing to fellow electors to put differences aside for the good of the church.

"My brothers let us pray that the Lord will grant us a pontiff who will embrace this noble mission with a generous heart," he told the congregation as many cardinals looked skyward as outside thunder and lightning and intermittent hail storms appeared to give gravitas to his words.

Black smoke at the Vatican signals that there has been no decision on a new Pope aftert he first round of voting att he Conclave.

He added: "Each of us is therefore called to cooperate with the Successor of Peter, the visible foundation of such an ecclesial unity."

US Cardinal Timothy Dolan perhaps saw it differently saying a calm had washed over him as if "this gentle rain is a sign of the grace of the Holy Spirit coming upon us."

Later in the afternoon, the 115 red-capped cardinals walked in procession two-by-two along the frescoed walls of the Vatican’s Apostolic Palace to be sequestered into the Sistine Chapel for the vote. As they entered the chapel they chanted what is called the “litany of the saints”, asking the more than 150 saints by name to help them in their choice of pope.

Once inside they bowed before the frescoe of Michelangelo’s Last Judgement then took their place to each swear on a book of gospels an oath of secrecy for the duration of the conclave, under threat of excommunication if they reveal elements of deliberations in selecting a new leader.

The whole chapel scene, before the cameras were ordered out and the doors locked with only voting cardinals within, was broadcast live on big screens about St Peter’s Square.

Prior to the lockdown, some cardinals took to the Internet and Twitter to say their goodbyes to followers for the next few days.

Tina Carreon (L) prays during Votive Mass that concluded the twelve hour prayer vigil in advance of the election of a new Pope.

“Last Tweet before conclave: May Our Father hear and answer with love and mercy all prayers and sacrifices offered for fruitful outcome. God Bless,” tweeted South African cardinal Wilfrid Napier.

It was a day steeped in history, holy ritual and tradition despite the unorthodox resignation that brought the world to this moment. And despite the rain that poured, at times torrid, throughout the day, thousands of pilgrims and tourists including from Australia have been enjoying what everyone appreciates is a very special week ahead for the Roman capital and Catholics in general.

With AP

Pilgrims in St Peter's Square watch a giant television screen showing a mass being held in the basilica.

A giant monitor in St. Peter's Square at the Vatican, shows cardinals praying.

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